We recommend purchasing a computer from an online store such as the above and having it shipped as the best option. You can, of course, also go to a physical store such as Best Buy (for PCs) or Voelker Research (Macs). We find online stores preferable primarily because the items are built to order and so are a bit more "brand new," they don't tend to come with as much pre-installed junk (called bloatware), and there are more options for configuring your purchase just how you want it.
We do not recommend chromebooks.
Prices for basic computers have really come down in recent years, and in the case of both Dell and Apple, starting with the cheapest base model and bumping up the specs a little bit is fine for the majority of things that an average person uses a computer for.
We suggest getting a solid state (or flash-based) hard drive that's at least 256 GB (512 GB is a safer bet) and 8 GB of RAM.
Here's an example dell laptop that will accomplish the normal minimum tasks that a CC student would need. It won't be the fastest or best computer, but it's a good deal for a very low price.