Bossypants by Tina Fey was really good and very funny. Bedwetter by Sarah Silverman was really funny, too and I also enjoyed Chelsea Handler's books, my favorite is probably Are You There, Vodka? It's Me, Chelsea.
If you want to go a little older, try James Thurber, one called School Daze particularly, hilarious and timeless. I was just recalling it as I watched Ralphie in Christmas Story the other day, same type humor from a similar viewpoint. Similar to Dave Barry as well.
Or go classic and read Mark Twain. Cover the date and you'll swear he is poking fun at today's issues.
When opportunity knocks it's wearing overalls and looks like work.
Non-equine, I love:
David Sedaris (especially Me Talk Pretty One Day)
"The World of Karl Pilkington" by Ricky Gervais and Stephen Marchant (actually, now that I think about it, I might read that again right now)
I'm also partial to Georgette Heyer's Regency romances, some of which really are hilarious at times, and are great for light 'n' fluffy... the best, I think, is "The Grand Sophy." "Fredericka" is also funny. Hmm. Now I want to reread "Fredericka" right now too.
The Hitchhiker's Guide to the Galaxy by Douglas Adams
Utter nonsense And if you survive that, there is the rest of the trilogy: The Restaurant at the End of the Universe
Life, the Universe and Everything
So Long, and Thanks for All the Fish
and Mostly Harmless
"In the beginning, the universe was created. This made a lot of people angry and has widely been considered as a bad move." -Douglas Adams