Amsterdam Coffeeshop Directory Forums

hello all, i will be in amsterdam from may 3 to 6. i will be alone at hotel anco and i would like to visit different coffeshops to taste rosin and wax. Do you have any advice for me? In particular I'm alone so I don't want to buy 1g every time but I look for places where I could buy less. I also read that May 5th is a holiday in the Netherlands, is there any event that I can't miss?
Thanks to all who will reply
Good day

Hope you are into remembrance day...pretty sombre event

why gloomy? They celebrate the liberation if i understand correctly so i think it's a good day. here in Italy there are many parties and concerts for liberation.