A creature could use tentacles. Octopus are quite good with their tentacles, they can open jars. By many measures, raccoons have better hands then we do, they use them to open shellfish. (and garbage cans). For that matter, have you ever watched a squirrel eat a nut? They aren't bipeds, and yet I suspect a sufficient intelligence using squirrel hands could do anything we can. Lots of rodents that aren't quadrupeds have pretty good "hands". For that matter, if a creature has more than 4 limbs, two could evolve into hands and stll leave 4 or more for walking.

I personally like aliens based on animals. There are lots of interesting animals on this planet, and it's interesting to try to extrapolate what they would be like if they evolved intelligence. Most of the time when people don't use animals as a base they come up with things that seem unlikely from an evolutionary standpoint. Of course, you can't keep the aliens too much like the animal they are based on. We changed a lot in the course of evolving intelligence. My problem with planet of the apes is we know EXACTLY what apes that evolved intelligence would be like. Us.