I have Mac OS X 10.6.8 but I do not have the mac app store.. How can I fix this?

Previously I had an issue with the Mac App store, it worked properly but then it stopped working. The icon had the little cancel sign logo on it in my applications folder, and if I tried to delete it it would say something around "App maybe be damaged". So from a previous post on the forum it gave a link to redownload os x snow leopard... it's not allowing me to download the mac app store at all.
Continuing my search I see people saying 10.6.6 should be downloaded not 10.6.8 ... Seeing that my os x is an earlier form compared to 10.6.6 that isn't acceptable to download in order to get the Mac App store back onto my laptop...

I want to know if this is something I can do or if I should give up and go back to the near by apple store and have them resolve my issue..