There are some packages and a lot of people use OpenLDAP but I also read that there are a lot of problems with it so I'm a bit confused. I have red hat and I was wondering what the best solution for LDAP was?
If you are using Red Hat I would recommend going with the "Red Hat Directory Server". I am using the CentOS equivalent and it is working just fine. It is the 389 Directory Server Project.
Part of the reason you will not find a lot on the 389 Directory Server is because of name changes.
You can read more about it at the 389 Directory Server home page at http://port389.org.
It was the Fedora Directory Server, then the "389 Directory Server" so that it was more distribution agnostic (it is still a Red Hat Sponsored project.
Red Hat uses the 389 Directory Server code to build it's "Red Hat Directory Server" and CentOS repackages that as the "CentOS Directory Server".
Other than the name confusion it has been pretty good. You will still have to be familiar with the linux terminal however.
The best documentation for it is still focused around the Red Hat DS, but it really does apply to all of them. You can find it here: http://www.redhat.com/docs/manuals/dir-server/
I would go with the package your OS provides (OpenLDAP, I guess), unless you have a good reason to do otherwise.
If this is the first LDAP server you set up, OpenLDAP is probably used most and thus best documented - googling "linux ldap server" gives 9 tutorials about OpenLdap and 1 for 389 Directory Server.