Start off slow with basic virtual PBX service features The world of telecom acronyms can be pretty jarring. If what you want is a receptionist and voicemail, small business PBX can be cheaper and easier to buy than fully-blown virtual PBX system or hosted PBX.

I recommend:  Take a look at virtual PBX software offerings along this line from vendors like eVoiceReceptionist, WorkEasy, Onebox and American Voicemail.

Complete virtual PBX systems are plenty and plenty competitive If you've priced a fully blown small business PBX system, take your bid and stack it up against virtual PBX software for a good comparison.

I recommend:  RingCentral, VirtualPBX, GotVmail, Freedom800, and VoiceNation can get you going on small business PBX for as little as $10 a month, depending on how many services you add to the basic virtual PBX software package. See more choices at the Business.com directory on hosted PBX and virtual PBX service.

Hosted PBX can bring a load of advantages besides cost Because it relies on your Internet connection to work, hosted PBX can put your phone calls into an integrated, always-on world. Track people down, have clients find you, assign numbers on the fly. The sky is (nearly) the limit, and even big vendors have small business PBX packages.

I recommend:  Some of the larger, business-class providers of virtual PBX include Avaya, Nortel Networks and Cisco Systems.

Cut costs dramatically using VoIP PBX Voice over Internet Protocol (VoIP) uses the Internet to route your business calls, a very cheap alternative to traditional phone lines for small business PBX. Given that the calls are already coming through a server, it's possible to add virtual PBX features over the Web using virtual PBX software.

I recommend:  Give the predictability of Web calling costs, some providers have move to billing virtual PBX service flat, simplifying the business decision. For more on VoIP PBX, take a look at Palavon, Aptela, and Broadcore.

Small business PBX for the very small business Some providers have structured their offerings around not just small business PBX but even single users. This flavor of small business PBX is good for independent contractors, real estate professionals and consultants, these plans have simplified Web interfaces, much like VoIP PBX, charge for a set number minutes, much like cell phone plans.

I recommend:  Some companies in this space includ ifbyphone and ConnectMeVoice,