V.W.
I have a Riccar SupraLite and love it. It's similar in price to an Oreck (and also weighs less than 8 lbs). It doesn't have attachments, per se, but it came with an over the shoulder unit (completely separate with it's own motor and bag) that DOES. My kids use it to clean out the car. I use it on curtains, lampshades, sofas, etc.
The upright vac is wonderful. We DO have a dog (a GSD, and they shed a LOT) and this vacuum gets dog hair up without a problem. The only "problem" I've had with it since we got it about 3-4 years ago is just regular maintenance stuff---the belt gets old/worn and has to be replaced. It's a do-it-yourself "job" and the belts cost about $1 each.
It has a HEPA bag, so they keep all the "particles" inside.
They have lots of other upright models, some of which do have a attachments. And after having the one I have, I would recommend any model they make.
http://www.riccar.com/products/uprights/
I bought mine through a local vacuum store (went looking to try out an Oreck and liked this better) and paid less than the website shows on pricing. Search around...there are compare features on the site to compare the different models they sell.
ETA: Even if you go without attachments, the one I have is so light that you could probably use it on stairs if you wanted to. It is a DREAM to push around. The vacuum I had before was impossible--I couldn't even teach my kids to vacuum b/c it was so awkward and heavy. This one, I taught them the day we bought it. SUPER easy and it WORKS.