Six months before my job went away at Thomas Nelson I knew that having to leave was possible. When bonus time came in the summer I set money aside and made three purchases that were the smartest money I have ever spent: I bought two quality suits and a MacBook Air. I did this because job hunting, aside from strategy, requires three things: appearance, mobility and communications. With these new assets I was able to send and receive resumes, applications and references, surf the web, and show up anywhere in the country on short notice looking like the job I wanted to find.
In my career as an interviewer I am constantly surprised and disappointed at how candidates present themselves. Now before you go jumping on me for insensitivity to people who are out of a job and can't afford such things, remember that I mostly recruit for upper level positions. This was true at my last job and my current job as well. If you are looking for upper five or lower six figures and that is what you have been accustomed to making, there is an expectation that you will look like a manager.
How you present yourself speaks to judgement, and judgement is one of the key factors (along with skill, intelligence and integrity) that companies look for in managerial candidates. Unless you are 20 and looking for your first managerial job at a small store or kiosk, the leather coat, dress slacks, black shirt and black necktie will not get you there. If you need to economize consider Goodwill or consignment stores that specialize in business attire. Otherwise make the investment rather than thwart all the strategy and energy it took to get you the interview.
...and for goodness sakes shine your shoes and bring an extra copy of your resume. These are fundamentals and they matter.