If someone or something whets your appetite for a particular thing, they increase your desire to have it or know about it, especially by giving you an idea of what it is like.
A really good catalogue can also whet customers' appetites for merchandise. [+ for]
...lectures he hopes might whet the appetite and keep students' enthusiasm.
See full dictionary entry for whet
whet someone's appetite
to make someone start to want something very much
Winning the World Championship whetted his appetite for more success.