I needed to replace start pully on a ryobi 700r trimmer and the recoil spring came undone and now I can't get it back in. any suggestions?

It can be very difficult, it is an acquired art holding onto the spring while winding, you will need a needle nose vice grip handy and just start winding. When you have it small enough to fit in grab with the tip of the vice grip. Other than this you could buy a new one in its own cage but no guarantee you won't unwind this one also.
Don