Good morning, Dan!
You inquire about experience with immigration attorneys. I have experience both with immigration attorneys and immigration consultants.  I was fortunate, both worked for me. As everywhere it seems to depend on the very person you are contracting. In general immigrations seems to be much easier here than in Canada for example.  If your wife is a Mercosur resident it should be much more easy. To finish this point for me the specific consultant worked better than the lawyer and she is less expensive too. The turn around time was very good and I always felt comfortable with her. She kept calm and minimized the effort, built bridges even where she had not been before. Very good interpersonal skills.
I live out in the country and have no problem whatsoever getting contacts although I do not speal Spanish at all. Uruguayos are very friendly and helpful people. The neighbours come to introduce themselves if you do not go looking for them.  I do not know how this works in the city. So I never looked for an online option to connect.
Hope this helps. If you come our way when you travel in Uruguay you are very welcome to visit. We are close Ruta 1 at the Western end of Colonia.
Armin