I don't often go and buy a book of poetry based on the author. I'll find poems and read them, usually by amateurs or unknown people. I like to go to deviant art and read the poems on there, I even post occasionally. I have also gone to poetry.com and read some of the stuff there, but for some reason I prefer deviant art. If I get tired of poetry, I can look at photography, prose, or digital art.
If someone finds a particularly powerful or moving poem, and they recommend it to me, I'll check it out, but since the internet is so good at pulling a single poem up for you, I'd have to really love the poem to seek out more by that author.