Hi,
There are many, many of them that offer free and also trials, with buy, software.
One I really like is:
http://www.cnet.com/downloads
Reason I like it is because it has User Opinions, where one can post how they like the software after trying it out. It's nice to read others opinions before taking the time to download/install something.
It also has a good search engine built in.
Best wishes.