As most of you already know, there are two different types of baby walkers; the kind your baby sits in and the kind your baby pushes (like a baby stroller). Both have benefits, it all depends on what you are looking for. If your baby is between 7 and 12 months and you are looking to help your baby develop those walking muscles, you might want to go with the stand up, mower type. If your baby can only crawl you might want to look more towards the sit in type. Both come with toys and gadgets for your baby to play with and learn, but the sit down walker seems to be a little more restrictive in the movements of your baby. This can be a good thing if your baby is not confident in his or her walking abilities just yet.
If you are looking for a simple walker that contains the wooden blocks and alphabet letters, you should look at what is available through Mischief. If you are looking for a more modern electronic walker, you should look for the Vtech walkers. Just so you are aware, most of the Vtech walkers are the stand up, mower type walkers. My personal favorites are the walkers from Leapfrog.
Find out what your baby needs, do some shopping around and have fun. As long as you are an observant, responsible parent you should have no problems.