I don't think that you can install fonts used on your PC to your phone. Most if not all of the Flipfonts listed in the Market are for sale, but you can install fonts on your phone free of charge and you don't need to root your phone to do it.
You will need to do several things, first go to Android Central and get the Android Central Sideload Wonder Machine (ACWM). You can use this to sideload applications without rooting your phone. Once you download it, extract the files so you can run them:
http://www.samsungcaptivateforum.com/sideload-android-apps-all-you-want-sideload-wonder-machineNext, go to XDA Developers forum and download flipfonts. I downloaded one with about 35 fonts in it, but I am linking to one that has about 70 fonts. Look for the link under the Extras heading:
http://forum.xda-developers.com/showthread.php?t=940514Here is a post showing what some of those fonts look like:
http://forum.xda-developers.com/showthread.php?t=942726Now, extract the fonts into a folder on your PC.
Switched your phone to debug mode (Settings > Applications > Development > USB Debugging).
Run ACWM and connect your phone to your PC. You will have to choose each font you want to install.
Happy fonting.