This sounds like the common ADSL and WiFi router combo's that ISPs supply all over the world. Your ISP usual has these. If not I'd ask another.
Your questions use too many acronyms and I may have missed what you are asking. For example the common ADSL router needs power and the phone line. Your question sounded as if you wanted ADSL without the ADSL connection with power only.
Is there any particular device(D), which can be plugged to an electrical outlet(E), and then serve as a adsl modem and wifi router(AW)?
1. E--->D(with adsl line connected)-->Transmits signals to wifi ready PC/LTP.
Most of the devices, I found on the internet, sits on the desk and has a power connection+ADSL cable+Ethernet/USB+/-wifi.
I want to jack in the D and then connect the wires, and get wifi on 2-3 computers.
This is what I have right now: