First, see several other StackOverflow questions that may help:
http://stackoverflow.com/questions/47366/sql-compare-like-tool-for-oracle
http://stackoverflow.com/questions/183730/free-oracle-development-tools
I'm sure there are several tools available for what you need; many come up in a Google search.
I use Quest Software's TOAD (Tool for Oracle Application Developers) at work. It's generally regarded as one of the best commercial options. It can be purchased in several configurations and has a pretty thorough and easy to use schema compare/synchronize.
Sybase's PowerDesigner is an incredible tool that can get you some of what you need (and a boat load more).
The Embarcadero suite of database tools can probably do some of this too, and they support several databases, not just Oracle.
But the above are not exactly inexpensive. Again, check with Google...there are some results that point to some free tools, but I've not tried any of them yet.
For your second question, here are more StackOverflow questions that might help:
http://stackoverflow.com/questions/77172/stored-proceduresdb-schema-in-source-control
http://stackoverflow.com/questions/115369/do-you-source-control-your-databases
http://stackoverflow.com/questions/287409/oracle-packages-in-version-control
http://stackoverflow.com/questions/308/is-there-a-version-control-system-for-database-structure-changes