Left that job to go to a start-up where I was introduced to the founders through a connection. The problem is that (initially to me) the position didn't seem sufficiently technically challenging to me (standard LAMP development), so my connection ended up both a) "selling" the position to me b) "selling" me to the founders (who in turned tried harder to convince me that the position would be interesting).
That's always a sticky issue with referrals: they give additional reasons for hiring a person and a additional reasons for the person to accept the position. The company will feel the referring employee will be happier and more productive if his friend/former co-worker is hired; the referred connection will want a chance to work with someone they already knew and enjoyed working with. Problem is that these reasons can detract from the real questions at hand: "is this person a good fit for the position" (for the employer) and "is this a position where I know I will be happy" (for the employee). Neither side should be trying hard to sell themselves. Note: obviously I am talking about engineering vs. sales. In sales the candidate should be selling themselves (they're expected to sell the product) and should have built up a rolodex of connections in the industry.
When it came time to leave the start-up (due to the office moving out of my reasonable commute range and lack of technical challenge meant I wasn't interested in moving yet again), I applied to four companies (three of them big names, one a mid-sized start-up)-- two by sending in a resume in response to online job ads (Dice.com, LinkedIn), one by a contact from a recruiter, one through a referral. Got interviews from all. Got offers from three and (after more sleepless nights than I imagined) chose one-- the one position I didn't get an offer for was the one where I was referred (yes, it was Google).
All of this happened in Summer/Fall of 2008, as the market was crashing. So, your mileage may vary. My tips are this: write your resume smartly (show that you're competent, don't tell) tailor the resume (and especially) the cover letter to show that you're passionately interested in that specific job. If you use the UDP Multicast method of sending a resume (blast out 100 copies of it to 100 different positions), as expected with UDP Multicast, don't expect it to be processed. Apply only to jobs you (judging from the job description) feel you will be happy to do (which will make displaying passion and interest in that position very easy).
Here are some good resume tips (although I've read them after writing my resume): http://steve-yegge.blogspot.com/2007/09/ten-tips-for-slightl...
http://www.globalnerdy.com/2007/09/26/steve-yegges-resume-ti... (in case your response towards the first link is "TL;DR")