create contacts

hi, i would like to create a contacts page where people can email their details, complaints, compliments, etc…also a tell a friend tab so people can send my site to their friends. Can you please tell me how to do this??? I have googled this and found a download but it is not showing up in the plugins after i have uploaded it, so something is wrong. could you please give me the details on where i could find what im after or how i would create a code to do these 2 things. Thanks Leonie