First go to the MobileRead wiki and find the articles on creating epubs - there are several. Then pop over to Liz Castro's blog
and look at her book on the right column. A very good $20 spent, and it does touch on problems caused by InDesign. Then you can poke around her columns, both interesting and useful.
Oh, and welcome to MobileRead. Don't forget to go to the Lounge when work is done