I don't know about the OP (original poster) but I want to give a big thanks to everyone who replied. I learned a lot. Especially

for Sigil (woohoo) and the links. I'm in heaven right now.
Now to the OP: I found Calibre very frustrating in the beginning also but if you take your time, read through the forum and just look around the program itself you'll find that it's not that difficult to use.
And Sigil is a separate program here's the link:
http://code.google.com/p/sigil/