Welcome.
Check out the Mock exam sections on the left side of Cameron's site:
http://studyguides.scja.com/ExamScam/get.jsp?link=books I used Head First Java, doing most of the programming projects in the book. I then read through the SCJA book at least 3 times. I also made myself flashcards, about 150 of them, based on the materials in the book. I also copied all the questions and exams from the SCJA book, so I could do them more than once. You would think you remember the answers, but there is a lot there. Even if you do remember the answers, isn't that the point?
For UML, there is a free guide somewhere, but I can't find the site right now. It was from Head First as well, as a filler while they were finishing up a book that would include it. I'm sure I found it through this site, so take a look around.
If you are new to Java, which I was, having not touched it for eight years, I think this could be enough. If you are failing the SCJP, I can see going for the SCJA. The merits of the SCJA are yet to be really quantified, but it can't hurt (although some say it can). Anyway, I am also trying to switch careers, and having that on my resume has attracted the attention of some recruiters, but I get the feeling they don't really know the difference between the SCJA and the SCJP/D, etc. Maybe that's good, maybe bad.
Anyway, keep going through it. The exam was difficult, but with those materials, should be passable. I would be curious what you used for the SCJP? that said, they are not really aimed at the same audience from what I understand, with the SCJP aimed more at programming, versus the SCJA maybe aimed at general wide-spread knowledge.
Good Luck
