1) I tried to contact someone to give them an offer for a domain, but the contact info wasn't accurate... is there really much of anything I can do?
2) if it's that easy to just have innaccurate info and get away with it, what happens if I change my contact info on domains to be something not-quite-real, to avoid contact/spam/etc? I'd like my info to remain private on some domains but 10$ a year (godaddy's service) for each domain doesn't sound all that great
You CAN input fake information on your domain's WHOIS if you wish. But you run
the risk of having it shut down, or worse deleted due to breach of contract.
Another option is to switch to another registrar that allows you to input 2 sets of
contact data, one for the WHOIS and another for internal purposes that's not
shown to the public at all.