Hey Dano, welcome to the forums! It's hard to know where to start with mods especially for a new minecraft player but thankfully there's a lot of knowledgable folk round here willing to help out the newbies. Don't be afraid to ask if you have questions on anything.
Here is a very good getting started guide which explains a lot of the basic concepts behind the various mods. I'm digging around for some old tips threads that would be helpful for you as well, I'll edit them into this post if I find them.
Edit: This is full of tips and this has a lot of useful links. Happy reading!
SMP Server Promotion is the place to go for servers, you'll probably be required to do a whitelist application for most of them though. Not every server expects you to be an amazing builder or whatever but having some examples to show will help your chances of getting a place on a good one.
You should definitly start with reading all the games posted in the "other games" section!
I would also recommend, for comedy value, this golden-thread that has been gathering dust in another forum. It's filled with much humour
And the author is kinda funny as well, I hear.
I think youtube is also a good source for anything that you can think of....
Welcome to the forums Dano, try taking a look at Direwolf20's new LP Season 5. He started off using Thermal Expansion and I think he took the best route (I'm following him on my SSP LP and installed GregTech, and ended up wasting 3 diamonds on a macerator when I could have gone his way >_<)