I would recommend purchasing a guitar and amp starter pack, such as the Ibanez or Ashton beginner packages, if you're just starting out. If you do in fact acquire your guitar and amp separately, have enough money and are planning to play seirously, I would highly recommend upgrading to a 30W amp straight away and forgetting about buying a practice amp.
Roland has excellent-quality amps, but Ashton and Laney are good brands for the customer on a budget. I've heard terrible things about Behringer, even though some of its prices are simply amazing. For example, a Behringer 90W amp is around $300 but that price would only buy 30W from other brands. While that is insanely cheap, it is also quite suspicious and could quite easily hint at poor-quality design.
Although I've never used one myself, I've heard that the Fender Frontman can be unreliable at times. There's a brand called Silvertone, which sells a 10W amp for approximately $99, if you're interested in cheap products.
Again, I would recommend purchasing a complete guitar/amp set over buying both individually. If you were to go with the second choice, however, you might as well buy a good-quality 30W+ product in order to save yourself from having to acquire another amp later on. That's, like, expensive, d00d.