Hi M.,
I don't know about adding jacks, however you can use splitters to get the cable going to more rooms. Find the source of the cable (basement, roof or another room). You can get a splitter from radio shack, best buy, they aren't that expensive. The best way to do it varies by house & the set up. I worked it so we had cable in 3 of our 4 bedrooms in my parents house by using a splitter. I was able to find one of the primary cables coming from the roof (they have a flat roof that you can walk out on). I used a 3 way splitter. One end has one input(main cable from roof) co-ax jack & the other has 3 output (one for a each cable leading to a bedroom). We ran ours through the window so it was always open just a tiny bit, but nothing noticeable. And hooked the cables up to the 3 separate tvs & voila, we had cable. Keep in mind, the more you split a cable signal, the lest quality picture you will get. It's a lot easier to show that to explain. I hope it helps. Feel free to contact me with any questions & I will do my best. :)Good luck!
PS - my DH is not handy either :) so I do a lot of the fix it work. But he does do laundry & floors when I ask! :)