Hey Comet,
Just wanted to throw in my 2 cents. I'm brand spankin' new to RIU and joined pretty much to respond to your post. I've been growing stuff for awhile and have had some issues with bugs/pests in the past. I have purchased several brands of soil and won't go into the ones I have had problems with, but for the last 2 years I have been using Happy Frog and not once have I encountered a single bug in that soil. Maybe I'm lucky, or maybe they go to great lengths to make sure their soil is bug-free, but either way, that's the soil I have settled on. If you can find it in your local garden store, that is the soil I would suggest using. You can mix your own and all that hassle, or like tntgreen13 says, you can bake soil to sterilize it, but for your wants and needs, in my opinion, just buy a bag of Happy Frog and be done with it.