Both my wife and I use l-arginine for sexual arousal and enhancement. It works for us. It's similar to over-the-counter arousal creams and lubricants. It actually feels the same but I think it works a little better. Results may be subjective though, I've seen reviews where people claimed that it didn't work for them at all.
I don't recommend buying l-arginine cream that's specifically labeled for arousal. There is basically no difference between those creams and other l-arginine creams. The "arousal" creams just cost a lot more. So you will be paying extra for no reason. It's a good idea to read the ingredients list and make sure that there aren't any additives that one may have sensitivity or allergies to. I always check these types of products on my hand first to make sure that it's not going to irritate me.