A great way to get started would be to look into if there are community gardens in your area. Many cities have them. A few places to try begin your search are
http://acga.localharvest.org/, your local Agricultural Extension office, or your local Parks and Rec. Usually you can rent a small plot for a nominal fee. Community gardens are also a great way to go for novices because you can learn from other gardeners in the same location.
If you have a porch you may also be able to grow herbs, tomatoes, peppers, or strawberries in pots!
Good luck!