I began by renting workstation space in a shared office suite with a company called Intelligent Office. Their service is outstanding and includes live receptionist service with a personalized firm/company greeting, mailbox service, conference rooms and offices rentable by the hour, and a shared copy/printer/scanner.
The workstation arrangement worked out fine for the first couple of months. Whenever I needed to meet with clients, I just rented an office or conference room for the meeting. After I got busier, I upgraded to an office. I recommend working in a suite with attorneys and/or other professionals as co-tenants. Fellow attorneys could be a great source of advice and referrals. Fellow professionals are potential clients.