If you are looking for a remote control toy of some sort for Christmas (& who isn't?), a remote control hobby shop if a good place to start. There are lots of online hobby shops that exclusively sell remote control toys, though I hesitate to call some of them toys. The benefit of buying from one of these sites is that because they sell only remote control items, their prices are often lower than traditional hobby and model shops, which sell a variety of things. Just check their return policy and you might want to look into shipping insurance if it's one of the more expensive ones.
I remember the Christmas my little brother got a train set. We set the track up in the kitchen, it was huge! If you're looking for a train set, try a railroad hobby and model shop. You'll have many different options available, from cheap to expensive, small to large, depending on the age and interest level of the person you are buying for. Unless you intend to play with the train set, or you're buying it for an older child, go with the mid-priced, small train set. You can always add on, but there's no need to go all out and build an entire town around the tracks. So my advice is to start small, but not cheap-cheap. You want to give the child a chance to enjoy the train set before it breaks.
There are hundreds of online hobby and model shops. How do you know which one to use? The best way to find a reputable online hobby and model shop is to spend some time researching. Go to hobby and model shop comparison sites, check consumer websites. Online hobby and model shops that don't have an actual building somewhere are sometimes not as concerned with customer service as those that do. If customer service is a concern of yours, I would advise you to try to steer clear of these sites. The only downfall of the stores with physical buildings is that the prices may be higher.

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