I have been trying to contact Hotel Aspen in Amsterdam but can not find a website and the email address in Rick's book gets returned as undeliverable. Anyone know what is going on or has a recommendation for a similar clean hotel (under 100 euros during high season) in central Amsterdam?
The domain name is for sale. They're clearly out of business.
Yes, Rick's Guidebook Updates indicate that it has closed. Here's the link, so you can see what else might have changed since your edition was published: https://www.ricksteves.com/europe/netherlands/guidebook-updates