I have my video on my pc, how do I use the footage?

Once you've got your mobile phone video clip(s) onto your computer, you might want to edit your material. Maybe you want to put a few clips together into a short movie, or use your mobile phone footage in a video edit together with DV footage. You could use one of the well known programs like Final Cut Pro or Adobe Premiere, that offer the features of a professional video editing application. The downside is that these are quite expensive.

If you can do with less, there are two free (as in price) video editing programs that come with the Windows and Mac OS X operating system:

Windows Movie Maker
http://www.microsoft.com/windowsxp/using/moviemaker/default.mspx

Apple's iMovie (included only when you buy a new computer, not when purchasing the operating system seperately)
http://www.apple.com/ilife/imovie/

There is also the (not-free) Ulead Video Toolbox (UVT), that offers a special version for mobile phone video users. UVT's Mobile Phone edition is specifically developed to edit mobile phone video. Using a PC, you can import/export and edit video clips in popular formats including AVI, MPEG-1, MPEG-2, MPEG-4 & WMV and output to these and 3GPP/3GPP2 - the most common formats for mobile video. UVT is only available for Windows, the Mobile Phones' edition costs $50.
http://www.ulead.com/vtb/runme.htm

If a very (very) basic editing tool is sufficient for you (and it might be when using mobile phone video), you may want to give Jumpcut a try. It's a completely web based video editing tool - everything happens on a website.
http://www.jumpcut.com/