Hi Russell
All the above is good advice. I'll also make the following suggestions.
You have set a reasonably high bar to do exoplanet work. Yes, amateurs are definitely making great contributions these days. But if you are new to photometry, then I'd start on something simpler and work up to the exoplanet work.
Start with doing some basic photometry work on variable stars. The suggestion (above) on occulations is also a good starting point. Once you are familiar with the software and equipment, then moving up to something like eclipsing binary stars would be my next suggestion - there are similarities between EB and exoplanet work.
If you want to get involved in photometry, then you should probably spend some quality time on the website of the American Association of Variable Star Observers (
www.aavso.org). They have lots of information and tutorials for those new to VSO. They also provide software and tools for members, and any data you submit is also used by other amateurs and lots of professionals, so you get a "feel good" feeling by participating as well.
The books listed above are also good references, and are on my bookshelf too.
In the southern hemisphere, Variable Stars South (
www.variablestarssouth.org) focuses on projects covering all sorts of variable stars (visual, DSLR and CCD) and there are projects involved in eclipsing binaries and indeed exoplanets that you can get involved in. I think that's a great organisation, and I learned everything I know from working with them. [full disclosure: I'm VSS's webmaster
]
There are plenty of people in both of these organisations that can provide assistance and recommendations, so you don't need to do it all by yourself. Your objectives as achievable, and the results are scientifically valid and can be published, so have a look at those sites and hopefully they can help you on the way.
I hope that helps you.