Welcome to the boards!
1) It is perfectly possible and acceptable and even FUN to have Human only fantasy campaigns.
2) Elves and Dwarves can be cookie cutter, but they don't have to be. I've got campaigns in which Elves were plantlike (something like the Woodling template) and Dwarves were actually carved from stone. And what stone a given dwarf was carved from affected their stats and affinities for certain classes.
3) For nifty races, check out books on world mythology, scour the boards, then use your own imagination. Personally, I've posted about the Elves & Dwarves above, but also about Fey who were actually Grey Aliens (think X-files or Close Encounters, etc.), Warforged who were like Cybermen or Daleks, Awakened Animals and re-skinning & reworking those river-dwelling halflings into a quasi-dwarflike race of sentient, bipedal Snapping Turtles to name but a few.
One of my favorites was the Nephilim. They were my (more flexible) take on 3.X's Planetouched- you know, the Aasimar, Tieflings, Fey'ri, and so forth. Essentially what I did was use Monte Cook's AU/AE rules on racial classes (themselves an improvement on Savage Species monster racial levels), and have a variety of menus that let you build PCs of all kinds of otherworldly heritages.
Others have posted about Celirians (sentient gliding reptiles), conversions for RIFTS Wolfen and others.
If that isn't enough or you find yourself with writer's block, just post a thread about what you're looking for in a new race and watch the suggestions roll in. There are a lot of helpful people here at ENWorld.