whenever I play a note, and lift my finger from the fret without pulling it off, the string keeps ringing, and it skrews up my tone badly when I play stuff on the high E string. The person from the guitar store said it was probably my cords I use to connect the guitar from the amp (they are probably the cheapest kind out there). Someone else said it was my floyd rose vibrating to much and that I should unskrew the plate under my guitar and put a piece of paper in under the whammy bar to keep it from vibrating so much. I would appreciate some advice.

this is the guitar I have

you might be pulling off slightly so when you play other notes it causes note bleed so sounds awful, people do it from time to time its hard to avoid all the time.

Gibson lpj
Epiphone Les Paul Standard
Epiphone Les Paul 1960's Tribute Plus
Schecter s-1
Marshall JCM900 100WATT HEAD
Fender mustang 1
Dunlop Crybaby
Danelectro Distortion
Tanglewood exotic electro acoustic
Westfield Bass
Nice guitar.

Does it happen on every string?

I'd tend to think it was just technique. Try deading the string when you've played the note before you bring your finger off.

There's a number of ways to do this, either with the palm of hand or the edge of another finger lightly muting the string as its fretting another. There are several ways to do it and there's no right or wrong way.

It may feel wierd or uncomfortable but in time you won't even know you're doing it.
It does happen on every string, and after I play a note and slowly lift it off and mute the string completely it still rings.