I thought it would be nice to have a smallish pond in my room. How would I go about making this? What would the dimentions have to be to be big enough for just a goldfish or 2
For just a goldfish or two why dont you consider a 10 gal aquarium. Failing that a half whisky barrel with one of those drop in black plastic liners would to the trick nicely. Flexible liner and a quantity of landscaping bricks of your choice would also work. Dont get carried away however, water is heavy and your floor might not hold the weight of too large a pond.
You can get a "tuff tub" from a tractor supply store, or elsewhere. They come in 40 and 110 gallon sizes. They also make round tubs. They are non-toxic. You can make a surround for it to improve the looks.
mali, i dont think your cats will be a problem. my sister has a 200 gallon in-floor "pond" in her room with 20 feeder goldfish. We have 5 cats and its never been a problem.