All you are doing with the cover letter is saying:
I want this job. I have experience so check out my resume. Call me!
They should contain three simple paragraphs:
1) I am responding to your opening.
2) Experience, desire, skills.
3) Call me
I am seeking the position of [job title] at [company]. I have attached my resume for your consideration.
My [x] years of experience [or training], as a [job title] qualifies me for this job.
I have utilized [skills] in my current and previous positions.
Please contact me at your earliest convenience to arrange a possible interview.
[email] [day phone] [evening phone]
February 10, 1997
Dear Sir or Madam:
In response to your advertisement in the New York Times dated 2/9/97
for a Programmer/Analyst, I have attached my resume for your consideration.
As a Consultant with over 3 years experience, I have had exposure to many
different technologies on both UNIX and Windows platforms. I am currently
employed as a Software Developer working within a Client/Server environment
with UNIX, C++, and Sybase. My salary requirements start at $75,000.
If my skills are of interest to you, please contact me by email at
firstname.lastname@example.org call me at (908) 555-1212 to
discuss possible employment opportunities within your company. Thank you
in advance for your consideration. I look forward to hearing from you.