Be a man get some tools & take that shyt off, then go on craigslist and get a used muffler. shyt is only about 4-10 bolts. 10 min job.
Easier said than done.
To the OP,
Don't bother welding a rusty pipe. You should replace it.
Well to do it yourself, you need to get a jack, 2 jack stands, sockets and socket wrench, 2x4 pieces of wood, and a cutting tool (hacksaw or Dremel tool with cutting wheels). If the pipe has rusted, skip the PB Blaster. The bolts are probably not worth fighting to spin off and it will be easier to just cut off and replace with new bolts, washers and nuts.
You can go to autopartswarehouse.com or wherever else and find a replacemet catback exhaust system for your car.
The 2x4 studs are used as ghetto wheel chocks.