If you're looking to patch some drywall along with some holes, depending on how big a job your have, you can buy a quart sized tub of spackle at the Home Center. Buy yourself a 4" knife. Use many layers NOT 1 big BLOB when you do the job. Scrape first with the knife (to knock off the 'high spots), then sand between layers. If you make any 'mistakes', scrape, sand, and spackle some more.
WHile you're at the Home Center, look into buying one of the Home Repair Books they sell. Read the index to see if they talk about drywall repair. If they do, check out that Chapter and see if it can help you. My best to ya and hope this helps.