Obligatory 'I'd rather have you' comment.
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I use Hammer. It's a part of the source sdk.
I use Hammer. It's a part of the source sdk.
Okay, I was going to do the same, but I can't find Hammer.
What do you mean you can't find it? It should be right where you left it after you used it to make a map.
I had to reinstall, so I can't actually see where I put the map.
Shit.
Default save location is:
\Steam\steamapps\xzzy\sourcesdk_content\tf\mapsrc\
With the xzzy replaced with your username, obviously.
If you didn't save that directory prior to a reinstall, yeah, you're boned. If all you did is reinstall Steam you might be okay.. Steam won't delete files in that area, only create ones that don't exist.
If you need any map decompiled for whatever reason I'd recommend bspsrc.
I've used it to decompile mvm_bigrock for you - http://dl.dropbox.com/u/84556731/mvm_bigrock_d.zip
Not sure how well it decompiled compared to the other maps listed here but I've used it alright so that's that.