Welcome to the forum Nvdiva ! You have joined in the middle of the summer-lull.So there is not much activity here right now. To find out the value of your stamps,you best have a look at some catalogue.If you have no printed one,you may try the "www.stampworld.com". There you can compare the catalogue values with actual selling-offers.
Look at stampworld or colnect for help. HOWEVER I was a seller on Stampworld and the prices are set by a few major dealers and they are not realistic. In any event looking at an online catalog to judge prices is USELESS as there is no pricing criteria based on condition. A $100 stamp quickly becomes a $1 if there are thins, creases, missing perfs etc. So the advice to check online is at best marginal. No one should pay catalog prices unless it is a very rare example or you have unlimited amounts of cash
