Years ago when I wanted some Unix utilities in Windows I got them from UnxUtils. Since then I've deleted them one by one because of various bugs. For example, I just found that find(1) doesn't find the files in one directory from one starting point but finds them from one directory deeper. The find from Cygwin works fine, though one has to get used to using Unix-style paths in Windows with it.
UnxUtils actually has a newer version on the project downloads page which isn't mentioned on the home page. I could try that but Cygwin is more widely used, tested and kept up to date. There's also MSYS from MingW, but Cygwin is easier to install and update and it can also compile MingW binaries which don't depend on Cygwin.
If you want Unix tools in Windows I highly recommend Cygwin.