I agree with hanseng1--Tradestation's EasyLanguage is very easy to get started in. Wealth-Lab is more for programmer-traders. If you can program in any intermediate full-featured computer language, you should definitely try Wealth-Lab, but if you are new to programming, start with Tradestation, Metastock or Amibroker (among others). After you have enough programming skills, you can go as complex/powerful as you want, including Wealth-Lab, Esignal, QuantStudio .NET, and on to homegrown systems you write yourself.
There is no free trial for Tradestation, but a good way to get started with ANY of the major platforms is to get yourself a subscription to "Technical Analysis of Stocks and Commodities" magazine. In the back, there is an entire section showing code examples for the systems and indicators discussed in that issue. You can read the article and then see how the trading system would be coded in Tradestation, Metastock, Wealth-Lab, Amibroker, etc. That will allow you to accurately gauge your level of programming understanding and decide which software platform you want to go with. Just remember that each platform has its strengths and weaknesses and that the more powerful platforms are often the least accessible.