I found the Free Range VHDL [1] book a nice starting point, it is open source, you can download it or buy a copy, it is especially useful if you have a strong background in software development, as maybe you case. I also found out VHDL easier to use at the beginning, it may me somehow overwhelming at the beginning, but its rigor also helps during the learning process. Perhaps the most difficult to understand is that when you are programming an FPGA you are really describing hardware and you have to learn to think in parallel. It also took me sometime to understand that not everything can be synthetized and downloaded into real hardware. Anyway, hope it helps and good luck!
[1] Free Range VHDL. The no-frills guide to writing powerful code for your digital implementations by by Fabrizio Tappero (Author), Bryan Mealy (Author), www.freerangefactory.org