If you cannot afford an attorney, you can ask the judge to appoint the Public Defender. Some of the best attorneys work as Public Defenders (though they tend to have heavy caseloads and can't always give clients the personal attention they want).
Attorneys are like doctors, plumbers and mechanics; the only thing they have to sell is their time and experience. Most can't afford to give much of it away. Those who do provide some pro bono service usually do it through organized programs, not to random people who just call on the phone.
In criminal defense, many lawyers say Rule One is "get paid first." If things go badly, the client will say a trained chimp could have obtained a better result, so you don't deserve to get paid... and if things go well, the client will say a trained chimp could have obtained a better result, so you don't deserve to get paid.
Please understand that this is a general discussion of legal principles by a California lawyer and does not create an attorney/client relationship. It's impossible to give detailed, accurate advice based on a few sentences on a website (and you shouldn't provide too much specific information about your legal matter on a public forum like Avvo, anyway). You should always seek advice from an attorney licensed in your jurisdiction who can give you an informed opinion after reviewing all of the relevant information.