I was going to post right after you created this thread, but I had to go research, and find the items I was looking for. Even stumbled upon a few new ones.
Going the free route will probably require more work than what could be done simply in Comic Life, but such is the way of free enterprise…
mjc covered balloons, and his are probably a better solution than what I was thinking of. For what it’s worth, I would like to suggest three free software that can help in your creation process.
1. Arts & Letters Express 7.0 DE (Download Edition; Free, not a trial/demo). Was very hard to find (well hidden). I use this software for custom text, and balloons. If used in conjunction with the next software listed, you can get nice clean vectors, and output alpha-ed bitmaps for end results. I also own (paid-for) 6.0 full suite as well (irrelevant to your freebie search). Download it here:
http://www.arts-letters.com/download/
2. Inkscape: Very good free vector software with many uses for comics creation. You can translate bitmaps to clean-line vectors, then back to bitmaps if needed. Download here:
http://inkscape.org/
3. Serif DrawPlus SE: Great vector/bitmap software to help with creations, but full functional crippled. It can be used to create balloons, stars, explosions, and etc. Only drawback I don’t like about this software is their registration process. If your system crash-n-burns, you change a hard drive, or do a complete factory rebuild, you will have to re-register with them again. Would be nice if they just sent you a permanent serial number with your registration. I own an earlier full version (though, not as nice; non-upgradeable) that came with my Print Master Pro software. Download here:
http://www.serif.com/free-graphic-design-software/
And, something that might be of use to you that I stumbled upon. You can download a few different page panel templates (PDF) for use to get you started, and then work on creating your own in the vector software. It’s a free online FLASH comic book creator from Marvel (for kids). Find it here:
http://marvelkids.marvel.com/games/play/75/create_your_own_comic
I hope this helps…