Ten years ago, I was doing the same thing for the phone company. Unless you can move to the CO, I&R work is a dead-end. No one in my telecom class is in the industry anymore, mainly to the stress of them treating contractors like migrant workers.
For me, I started doing DSL installs and learning everything I could. I bought the CCNA book and studied my ass off. That got in the door with an ISP where I wear a lot of hats. One of the reasons I was hired was due to my experience with doing telecom work. Installing jacks, switches, routers, wireless, etc is a lot like telecom except that now you have to configure them in addition to installation, not to mention troubleshooting, support and defense.
As for you, it depends on what you want to do. Security, networking, wireless......the choices are endless so you have to pick an area to focus on. Doing a search on monster or careerbuilder will help you narrow your choices. Monster recently had 12 results for CWNA and 215 results for CISSP. While I highly value my CWNA (it was the hardest test I've ever taken), it seems that I should go for the CISSP if I want job security in a down economy. It seems to me that, in a down economy, desperate people are likely to do desperate things, making security certs all the more valuable.
Other areas that are going to explode is LTE and fiber. MPLS is good if you want to try and move up in the phone company. See if they will sponsor some advanced training.
ISC2 Associate, WCNA, CWNA, OSCP, Network+