International / travel SIM cards available in London?

I don't think there really is an international SIM, per se. What the companies that sell these do is give you a telephone number that is tied to one country in Europe, usually in the U.K. Then you simply roam when you are in other countries. The rates you pay in those other countries are more than the rates you'd usually pay when roaming on a straight up SIM from a U.K. company. The one exception I can remember is one of the Telestial plans where incoming calls were free, but it had a high initial cost and there may be some fine print to the deal I haven't seen. (Telestial has lots of plans so you need to look carefully.) Anyway, the point I'm trying to make is just buy a SIM from a U.K. cell company. You can do that almost anywhere in the U.K., including, I believe, the airport. Then load enough pounds credit on the phone to cover the rest of your trip. In a pinch, you can buy top-up credit off ebay U.K. (the seller will email you the code; you'll need a paypal account). You then should be able to use that phone number everywhere in Europe. I say "should" because I haven't tried this yet. I will be doing so before your trip, so I'll try and post an on problems, if any, from doing so. By-the-way, I am using T-Mobile U.K. They have decent European roaming and roaming data rates. I haven't researched Vodafone and the other companies in detail. They should have similar deals, though.

Geoff, You might want to check the websites for some of the "travel phone" firms, as many offer Blackberry plans. As Paul mentioned, many of these use SIM's based on UK networks. However, the difference is that if you purchase a SIM in the UK, you'll be "roaming" when you use it in other countries, and the rates will change. If you purchase a SIM from one of the travel phone firms, the rates will be the same regardless of which country you travel in (although rates in some eastern European countries may be higher, as they're considered "Zone 2"). Check the websites for Roam Simple, Call In Europe, Cellular Abroad, Telestial and Mobal. As I recall, some of them have Blackberry plans. You'll have to decide if the rates and features are what you're looking for. Happy travels!

Have a look at Lebara SIMs. I don't know how their roaming rates compare to those of T Mobile. Their international call rates are pretty competitive. http://www.lebara-mobile.co.uk/prepay/rates

I haven't looked specifically at the Blackberry plans, but the rates for calls in what we might think of as conventional Europe are capped by the EU. Outgoing calls are around $0.65 I believe and incoming calls are around $0.24 at today's exchange rates. So Ken is correct, yes, you will be "roaming", but depending on the company, it may be a better deal than with the travel phone firms. It may not be that much of a better deal, I'll admit, but you have to wade through all the different plans to try and figure it out. Look at cellomobile.com. They mention Blackberry data and the rates listed are very good. I've not used them, but the Graffiti Wall had a few good comments about them. Of course, you've asked about buying a SIM at the airport, so you may not want to get a SIM elsewhere. If you buy one at the airport - if you can - you probably will not be able to shop for the best deal. It would be helpful if users of the travel SIMs would post their experiences, including the a) upfront cost, b) cost per incoming call, c) cost per outgoing call to the EU, d) cost per outgoing call to the U.S., e) cost to send and receive text messages, and f) cost to use data.

Thanks for the informative replies, everyone. One additional point I should've mentioned upfront: we probably won't use much data, so I'm not too concerned about that. Anyway, from the sounds of it, seems like roaming on a UK-issued, UK-based SIM card would probably be a reasonable choice. However, I do like the idea of using one of the recommended sites to purchase an international SIM here at home -- in particular because it will allow me to get my new phone number ASAP before we leave, which we can then relay to our hotels, restaurant reservations, and tour guides ahead of time. Cellomobile looks interesting... Though I can't find much info about this on their site, they make mention of the ability to "keep your number" (I wonder if they just mean "have the same (new) number with you in all countries you travel to"?). Their rates look good, courier shipping of the SIM card to Canada appears to be only about $10, and the minutes never expire. Their online purchasing system is down for some kind of maintenance right now, but maybe I'll check them out in more detail tomorrow. Thanks again!

I bought a Orange SIM card in Spain and it worked fine in Portugal and Belgium.
http://www2.orange.co.uk/servlet/Satellite?c=OUKPage&cid=1044131837837&pagename=PersonalIR

Thanks once again, everyone. I decided to give Cello Mobile (ttp://www.cellomobile.com) a shot. US$29.00 gets us an international SIM card with a UK number. US$10.00 for 7-day couriered shipping to my address near Vancouver, Canada. Not more than 20 minutes after I placed the order, I received a phone call from one of their representatives just confirming my order, and going through a few details regarding the SIM's use overseas. Pretty impressed with that! I should've double-checked, but I think the rep said that the SIM card would come with $10.00 pre-loaded, and whenever the value goes below $5.00, it's automatically reloaded in $30 increments, charged to my credit card. So, we'll see how this goes... next step, to unlock my BlackBerry! :-) ~Geoff

Thanks Geoff. Please keep us posted on how things work out with this company.