Practicing Speaking

I’ve been taking German classes for six months already but I am not quite happy with my speaking skills. Lack of vocabulary makes me stumble a lot. I need to practice speaking also outside of the classroom, but all the Germans I know speak fluent English and I feel uncomfortable asking them to speak German because I don’t want them to feel that’s the reason I spend time with them.

I am also concerned that when I leave Germany I will forget everything. Language needs a regular practice. So I was thinking maybe to try Rosetta Stone. According to its reviews it’s supposed to be fantastic. Has anyone tried? I would like to hear more about its effectiveness. I imagine it definitely can improve my listening comprehension but I am also concerned about speaking.

So, if anyone has ever tried Rosetta Stone, PLEASE, leave me a comment or recommendation about it.