Take this however you want to....
I got my first 121 interview this way-
I cold called the chief pilot and said I wanted to fly for him. He asked me how much time I had and then hung up.
I sent him a resume (WITH a postcard that was self addressed and stamped).
When I recieved my postcard back, I called again. He hung up again.
I sent a resume via email
I then called again to verify he had seen my resume. He started saying how I was unqualified, yadda, yadda, yadda. He then proceeded to say he was busy and ended the phone call with a goodbye.
A week later he called and offered me an interview.
2nd 121 job-
I faxed a resume.
I mailed a resume.
I placed follow up phone calls for each one.
I visited headquarters for the company and talked a line pilot into taking me to the Director of Ops.
The Director of Ops told me to get more flight time in a 152.
I walked in another resume to HR 2 months later. I chatted with a lady about my goals while handing my resume to her.
A month later she called me for an interview. Turns out she was one of 2 people that interview pilots for th company.
Do you see a trend? Tenacity and persistence show a strong desire to work for said company. Don't take "no" for an answer and don't be worried about making a pest of yourself. If you are being a pest, they will tell you. And when they tell you that you are being a pest...that just means they now know who you are.
This is all just my opinion and we know all know what that is worth. I would visit a "bit" more often than every 2 months. I would be in there every week to at least say hello. Make them put a FACE with the name! Update them on what you've been doing to improve yourself as a pilot (ie studying, flying, etc.)
Don't walk in the FBO acting like a wiseguy. That should go without saying. Walk in, dressed appropriate to the job, and leave an updated resume. I think you waited too long. I see nothing wrong with going over once a month or so.
You do have to be persistent. After a while, though, if you constantly get the cold shoulder, look elsewhere because it just may not happen at that company. I know. I tried for six years to get an interview with SkyWest, GP-Express, Horizon and at least one or two other commuters. Not to mention all the commuters who which I sent materials and updated for shorter periods. I sent in apps, resumes, updated resumes, new apps, had a former student walk in materials to SkyWest, and got zilch.
Just hang in. It also helps if you make friends or develop a relationship with someone at the FBO to vouch for your being a good guy, etc.
Most of the jobs I've had ( aviation and business ) have been obtained by visiting the office, calling those who make the hiring decisions, and showing the prospective employer you WANT to work for them.
The early bird AND the bird who follows up catches the worm.