Trouble with downloaded iso (?) files

[georgethecat]

Hi everyone! I'm new in the forum and yesterday I downloaded Dolphin emulator to play my beloved Gamecube old games.
I tried to search on the forum but i didn't found nothing helpful.

I have one problem...I downloaded some games (PSO ep 1&2, Smash brosh melee, PSO ep.3) and the only one I found with a correct Iso file is PSO 1&2.
The others games, when I have unzipped the zipped folder, do not contains any ISO files but lots of unknown (for me) types of file.

For example in PSO ep.3 folder the are only "tf-pso3.008" (numbers from 1 to 18) and tf-pso3.nfo and tf-pso3.sfv files.
I'm a greenhorn with Dolphin and Is the first time for me that I try to use emulators on OSX (mavericks)...so how I can get ISO file from these files?

Thanks to everyone want to help me, and sorry for the bad english!

[deadlegion]

Those are split archives. You extract from the first part, in the example pic you posted you would extract from part .001 using 7zip.