Day trip to Madrid from Barcelona?

'I'm seeing tickets on Iberia for $38 each way' - Plus costs and time expended to and from and in those airports, when the train journey is centre to centre. (I am not advocating either way.)

Zaragoza, an hour and a half probably, by train.
Why not just take the map and google, not neglecting looking at the images? Whether a journey would break your bank I would not know.

Day tripping to Madrid is kind of far. It normally take about 2.75 - 3 hours one way and costs roughly $160pp one way. If you were going to do Madrid, try to spend at least a night there to make it worth while. Any longer than 3 hours one way is too far for a day trip. Other good options for places closer to Barcelona would be Zaragoza, Girona, Figueres, and Montserrat. Flights can definitely be cheaper, but when the train takes as long as a flight does (consider trans to and from the airport and waiting time), it makes more sense to do the train as it goes from city center to city center.

I hope this helps some.

Tarragona perhaps? Short train ride south of Barcelona.
http://www.spain.info/en/que-quieres/ciudades-pueblos/otros-destinos/tarragona.html

To get a taste of Madrid I would recommend an overnight at least.
The following AVE trains would give you 32 hours on the ground in Madrid.

07:05 DEP BARCELONA SANTS
09:50 ARR MADRID ATOCHA
2h 45m Direct

18:00 DEP MADRID ATOCHA
20:30 ARR BARCELONA SANTS
2h 30m Direct

Thanks for all the suggestions. I ended up booking a round-trip ticket on Iberia airlines, which was only $78 total. I know I'll have to pay more to get to and from the airports, but that's not anywhere near the amount it costs to take the train roundtrip. I also ended up booking one of RS' recommended hotels in downtown Madrid for two nights. I believe it was only $29/night. So, even though I have to go through the hassle of airports instead of the convenience of trains, I think it'll be worth it to be there for almost three full days.

You can get deeply discounted train tickets if you buy them early (too bad you have already booked flights). Last year I got AVE tickets from Barcelona to Madrid for 39 euros by buying them about 40 days out. A taxi into town from Madrid airport will cost you about 30 euros, the Aero City Van is 20 euros. There is also an express bus that costs 5.50 euros but stops only two places once leaving the airport - Cibeles and Atocha train station.

Thanks for for this this information. As I myself will be going to Spain in October.

I still can't seem to find a good price does the train to a and FROM Madrid from Bcn.
Any thoughts on the best way to get to Venice as I am also planning to visit Venice for this trip. To cover Madrid Barcelona, Venice. Florence on on such a abort time lol.

Any thoughts will be appreciated

Yes, Madrid is worth a day trip. The high speed train from Barcelona arrives at Atocha station and the only sight worth seeing, El Prado, is a short walk, a couple of blocks, from there.

I'm being somewhat facetious. I'd rather spend a weekend in Toledo (with a day stop at El Prado).

Girona, mentioned by Abe, is just an hour away by train, and is well worth the visit, with evocative narrow stair passageways within the upper old town, and a great lower town, too.

With a nod to Brad, Madrid has at least 2 or 3 other things worth visiting ;-), plus great day trips of its own. If you can make it back to Spain, you could devote a proper amount of time to Madrid and the surrounding area, and/or Andalusia in southern Spain.