So I'm familiar with what goes into making a vanilla Modloader mod in MCP, but I have no idea how to set up mcp to recognize IC2 as something I can draw from. Can anyone tell me how to do this?
I've found the API posted elsewhere, but I have no idea what to do with it.
Copy and paste the classes from IC2.jar into the minecraft jar in your mcp/jars/bin folder, then run decompile. You'll need to do quite a bit of work to get IC2 to recompile properly - MCP doesn't like decompiling enums properly, for one thing, so classes like Direction need to be rewritten.
Check my tutorial in the support forum: [tutorial] How to decompile IC2
But weren't you supposed to use the provided API so that you didn't have to decompile IC2? I'm not an experienced modder (let alone IC2 modder), but the API thread has come up enough time for even me to notice it.
The API can be downloaded on this site: http://wiki.industrial-craft.net/index.php?title=Download. But if you need more detailed instruction on how to use it, I'm afraid you'd have to ask some more experienced modders. 
There are some thing one would like to change in IC2 that the API wont give you access to, but thats a little of grey area i think.
last time i looked at it the api is deffinitely not enough to make an ic2 addon, that merely gives you a way to make stuff you add in seperately work smoothly with ic2, if you want to make a ic2 addon you should definitely decompile it,
there is a tut in released addons section for that (kind of odd place for it )
edit: the api has been expanded and is now plenty for most addons
