What is the best way to mine litecoins.. since they are scrypt can gpus mine them just like btc?
Yes. FPGA and ASIC can't currently mine scrypt as it's very memory and energy/heat heavy. Personally I think AMD will always outpace scrypt FPGA and ASIC development just as byproduct of gaming on a $/k/h basis.
Some are looking now to develop FPGA's for scrypt but I think by the time they get it to market AMD will have HD 9000 series out with x4 the amount of shaders as now and 50% less power consumption.
M