Let's start with the basics. What do you need to give yourself a manicure? To start with, you need a good nail polish remover, cotton balls (never use toilet paper or paper towels - you will go throw a lot more than using a couple of cotton balls.), and quality nail polish. You should also purchase a small manicure set if you don't already have one. If you plan to go on the glamorous side, you'll need professional manicure kits such as ones containing French manicures, or acrylic supplies if you plan to add tips to your existing nails.
You can purchase the basic items at any local drug store or discount department store. Choose a nail polish remover that says "salon quality" on the label. You may want to consider using a non-acetone based remover, as this causes less damage to your real nail. There are several polish removers available that are low-odor or odor-free, and these are highly recommended if you have children or pets in your home. When choosing a nail polish, choose a brand that is common and avoid generic or store-labeled brands. Cheaper nail polishes tend to chip much faster than the name brands. You can even find professional quality nail polish at the local grocery store. One bag of cotton balls cost less than $2 and will last you a long time when doing manicures yourself.
Most grocery or local department stores also carry small manicure sets. These contain essential items such as nail clippers, nail files, nail scissors, and cuticle sticks. A good manicure set is usually found for less than $3 and with proper care, can last for several years to come. You can also find items at these stores for the more complicated manicure, but those items should be purchased at a beauty supply retailer. For example, when giving yourself a manicure that involves the application of acrylic tips, you should find those items at professional beauty stores rather than your local grocery store. These products are much better quality when coming from a professional retailer, as they are usually the same products used in nail salons. You may pay more for these items, but you will find that you'll be much happier with the result.
To find a professional beauty retailer in your area, simply look in the yellow pages or perform an online search. Nearly every major city has at least one of these types of shops. Some places will require you to have a cosmetology license in order to purchase from them, so call ahead to see if there are any such restrictions.