Most people use their Soft phone with a headset. This allows for better audio quality and more privacy than using the built-in speakers and microphone on your computer.
There are many options out there for microphone and headphone combinations. You can purchase one at stores like Target, Fry's, or Radio Shack. You can also order a headset online through stores like Amazon.com.
Logitech Premium Stereo Headset with Noise-Canceling Microphone
Plantronics Oth Mobile Headset 2.5 Connector (hearing aid compatible)
PLNMX150 Cellular Headset, Noise Canceling Microphone, 2.5mm Jack, Black
Additionally, if you have a hands-free for your cellular phone, this could be used as well. (This is true for most cell phones with a standard 2.5mm jack, but not for Nokia headsets.)
Most computers use 3.5mm (3/32") jacks for audio. You may use a headset with microphone that is intended for a computer and has two audio jacks, one each for microphone and headphones. Alternately, you can use a headset that is intended for use with a cell phone or cordless phone if you use a 2.5 mm to 3.5 mm (1/8" to 3/32") jack adapter in the headphone jack. These adaptors can be purchased at Radio Shack or Fry's for less than $5.
Another option beside headsets could be a personal speakerphone for your computer. We have tested and can recommend two options:
The Chat™ 50 personal speaker phone provides crystal-clear, hands-free audio communications. It provides full-duplex capability, which allows users to simultaneously speak and listen without audio cutting in and out.
The Polycom Communicator C100 features hands-free audio and can be used with stereo headphones for private conversations. It has full-duplex, high fidelity voice quality and supports up to 22kHz audio for CD-quality music and presentation audio. It has two microphones to ensure that others on your call can hear you clearly and to make the device flexible enough for group conversations. It connects via a USB cable that stores inside the device. It is pocket sized and comes with a convenient carrying case.