Hi. Matt gave you some good advice. To add to it, do some reading. Go to the main page, read the beginner's page. Theb from the main page, go to weight training (take the link) and it will show workout template, and they give advice on how to set up weight programs, and will link you into the Exercise and muscle Directory, where you will find descriptions and video clips of the different exercises. You have DB's so you can find the DB version of a given lift. Also, the tubing you have is very versatile. My Dad uses thm. Just be a little creative, hook on end on a door, or from the ceiling, or maybe even on the floor. They can duplicate most movements. You will probably come up with something along the lines of Squat, bench press, bent row, abs, low back, then maybe some arm stuff or pressing. I would advise you take your time, learn the exercises, and do a circuit style workout to start off, 1 set of each, resting long enough to change weights, rest after the circuit, and maybe go through it once more. That should be good enough to get you started for a few weeks.
As to cardio, it's explained very well here on the site. Find the links on the home page. Like Matt says, do it after weights, or on different days.
Check out the nutrition section as well, thats key for fat loss.