1) Independent Freelance Programmers

These call themselves "consultants", but in the end, they are just programmers, they take an assigned task, have a specific input request, and output a specific result. These types very closely marry themselves to a Statement of Work with a very specific job to do. I say they "call" themselves consultants because they really are not a "consultant" in the sense that they don't actually consult, or suggest anything.

I recommend: Market your business (or shop for) on sites such as rentacoder.com or elance.com.

2) IT Staffing Companies

(or headhunters) for the purpose of marketing, sometimes will call themselves "consultants". But when a customer is in a real need, but they don't know what they actually want when it comes to skill set, no set architecture in place, ... then the IT staffing company really cannot fulfill the need. They want to know "do you want an SQL programmer, VB, PHP, programmer..?"... But when the customer doesn't know, they can't actually help them.

I recommend: Research industry specific IT Staffing companies that you may align yourself with. All IT Staffing companies are not the same... thier recruiters will have specific knowledge and insight within certain industries.

3) Solutions Analyst / (Still overblown programmers)

These are programmers that have some business sense, but in the end, are just trying to get the programming job, and work hard to sell their customer every step of the way that they can customer program everything.. and they know how.

I recommend: Solutions Analyst are a step away from programmers... and take a certain level of higher expertise. Market yourself (or shop) on ework.com

4) Implementation Consultants

These are programmers that work for a software company, and they have a high-level of knowledge of that specific software platform. Highly stylized, they can also custom fit the platform to fit the customer's needs.

I recommend: As they are specific to a particular software, align yourself with that software vendor. See if they have a comprehensive partnership program. (Microsoft and Oracle for example have very good programs). If you are shopping for an Implimentation Consultant, contact the software vendor directly for their recommendation.

5) e-Business Consultant

This is the consultant that assumes nothing and takes nothing for granted. They are not looking to "accomplish" anything. They align themselves with the business owners or decision makers and work with them to design technology around their business need. They don't do the actual work, and many times may refer the work out.

I recommend: e-Business Consultants are a different breed, and will require more scrutinty. I suggest interviewing e-Business firms much like as an individual employee. Much of the solutions that they arechitect can likely change the entire course of how smoothly your IT infrastructure can run.