Is there a PPA for MySQL 5.5 for ubuntu 10.10 and 11.10?
Funny thing. Someone in another post suggested going to this URL:

https://launchpad.net/~nathan-renniewaldock/+archive/ppa

I got that link from this DBA StackExchange post by @galador:

https://dba.stackexchange.com/a/9476/877

Give it a Try !!!