I have just been put onto standupbootcamp which is a blog run by Kyle Cease. He also runs courses in the States, not very helpful for me, but check out if you can.
Here is a talk by Tom Wilson, Biff from Back to the Future Butthead! He has been working as a stand up for 30 years and says some interesting things about trying to become a stand up comic. It is in two parts.
Part 1 from Stand-up Boot Camp on Vimeo.
Tom Wilson Part 2 – Stand-up Mastery talk from Stand-up Boot Camp on Vimeo.