The internet is a good place to start looking for such summaries, but you should always be careful when selecting your sources. You could be wasting time trying to understand what somebody who actually knows less about you about law tried to express in a case brief, which defeats the purpose. The internet is a vast place though and besides junk articles, there are also high-quality briefs written by legal practitioners and experts, with the only downside since you have to pay for them.
On the flips side, the amounts these websites charge are incredibly low and for a handful of dollars, you will have unrestricted access to top quality information. If there is one thing worth investing in, then this is education and gaining access to any case brief you might need while in college make the few dollars spent an excellent investment. The best thing is that you will be able to use that information right away, without doubting the quality or trying to understand what the author tried to explain.