You might check the import export wizard found in the reskit. This will
export a workspace  to a file system then you can import to a workspace.
There are some limitations though such as discussions not copied as well
as portal customizations.

check http://www.nse.com/knowledge/ SP manager product. This will be
helpful. I have not tested the tool yet...

I'd have to warn some about nse. Today I received unsolicited spam about
their product. The only thing I can think of is they scanned this newsgroup
and/or the microsoft newsgroup to get a bunch of email addresses. I'm
guessing others on this group received it as well.

I sent a nastygram to their sales dept, and I encourage anyone else out
there to do the same.

Has anybody used this tool from NSE? Does it restore everything
including all customizations?

I've tested the personal edition. Doesn't backup the dashboards. The
product concentrates documents along with the profiles and
attributes, security and version. Surprisingly easy to use and of
some use, but not as a backup tool. I use it to quickly copy
missing/deleted documents after restoring  on a recovery server. I
also tested the avepoint tool and wasn't impressed. Didn't like the
ui and had some issues restoring individual items. The one I'd
really like to try is the commvault offering.

I have used the tool from NSE and no it doesn't restore all of the
customizations. It only restores  files in the Document Library.
The actual customizations you have made to web parts and other files
do not come across. However I still find the tool a nice one to
do backups of documents. I am waiting on the next version so I can
really see what it has.