+1 for what ano said. X-10 sucks. I had it in my old house and it was garbage. Not only did I have communications problems, but I had one switch actually melt. It was so cheaply made that I was afraid it was going to burn my house down. I don't know if this has ever happened to anyone, but I don't feel comfortable using that stuff.
If you're just buying a couple of devices to test with, it's not a huge investment even with nice switches. Go for something like UPB or Z-wave. If you decide to move to something else in the future, then you still only have a small investment in them.
Here's where I would start though:
- Find out what kind of alarm system you have and if it provides any home automation capability. It probably doesn't if it's not an ELK or HAI unit
- Find out if the system you have will interface with CQC or HomeSeer. If it will, you'll probably have to get a serial port expander or an IP interface for it.
- Evaluate CQC, HomeSeer, J9 Automation Engine (commercial), or Domotiga and MisterHouse (open source/free)
- Get a couple of test switches (UPB or Z-wave) and play around with everything
If your alarm panel does not provide some HA functionality and will not integrate with any of the software, then you may wish to consider getting a panel that does. I'm doing all of my home automation with my ELK M1G right now, and a copy of eKeypad for the iPhone for control. I don't have a separate software package running right now. A good panel provides the inputs and outputs for data gathering and control, and if your PC dies, can still provide control of your house.
If you want to play around with switches, then go buy some decent ones to test with so you don't get frustrated and pissed off because they suck. But, I think your #1 priority should be researching the capabilities of your existing alarm panel and figuring out if it will integrate with a software based automation engine, and if it won't, then consider upgrading it.
I originally started out with just security in mind. I bought the ELK M1G. After reading about all of the capabilities, I very quickly started putting in automation rules and controls. My next project is to use it for pump control on a hydronic heating system so I don't have to spend $350 for a pump controller. Speaking of which, I need to post a question about that now.