I have tried a few builds. I have ubuntu 10.04 on my laptop, dual booted beside windows 7. I can use it ok.
Thats great,i have just about the same i just use a older version of ubuntu9.4 and win XP<-love it even tho most don't.I use both to dev.
As for a good start point to learn read this http://forum.androidcentral.com/hacking/6037-general-rom-faq.html
I sign everything in windows,just seems easier(rigth click to sign things).
Then get use to writeing update scripts(can be a pain till you get use to it).Make sure you have notepad++ for making update-scripts,editing build.prop.
Other then that do a lot of reading(go to gb's profile and read all his how to/guides he does a great job at explaining almost everything.
Also just know how to laugh at yourself when you make mistakes.A lot of trial&error is how i learned alot.Don't be afraid to rip something apart and try putting it back together.If you need help hit my pm anytime and ill gladly help you out anyway i can and if i don't know it then we'll learn it together.