One way of doing it free is if you have XP you'll have Windows Movie Maker, you can join video files in that, however WMM will not accept import of MOV files so you will have to convert the MOV files first into a format that WMM will accept, you could download the free mov to avi converter
convert your files into avi then import them into WMM and join them up, you won't be able to save the joined file in WMM as a MOV file, WMM mostly offers saving as a Windows Media Video file that will play in Windows Media Player.
Otherwise you could download a free trial of a video editing programme and use that to import the MOV files into, most video editing programmes will accept the import of MOV files and then join them up and save the file as a MOV file if you want or any other formats that the programme offers which usually includes DVD video format if you want to burn to DVD later.
You could try a free 15 day trial download of Arcsoft Showbiz DVD, I use it myself and it accepts MOV input and you can save the joined files as MOV if you want to stick with the MOV format.
Another way is to download Super Converter
and use it to convert to mpeg1 and import the mpeg1 files into WMM.
I can't seem to find any free MOV joiners online but hopefully another forum member will.
Also download Gspot to analyse a clip and give you some idea of the clips properties before you begin