How do I improve my job searching/networking skills?

I’m going back to retail, which I swore I’d never do, but I’ve got to do something. I’ve been concentrating on school lately, but I’ve got to wait to get accepted into a program. It’s alright, but I definately need to improve my networking and job search skills. I’m expecting to get a couple part time jobs.

Is it better to go into the store, ask for the manager, and ask about hiring? Or just go in and get an application? Stay home and do it online? Attack the job search engines? I’ve never had much luck with them. Should I turn in a cover letter and resume with the application?

This looks like a lot of questions, but I really want to get better and do it right.