Some 6,000 temporary staffing firms nationwide fill more than 11 million jobs a year, analysts say. The agencies range from global giants with many business units like Kelly Services Inc. and Manpower Inc. to local niche firms that serve a single industry sector or even a single client. Whether you’re looking for an immediate job as an unskilled laborer or an overseas assignment as an emergency room nurse, there’s likely an agency that suits your talents.

To start with a detailed list of staffing firms in your area, check the American Staffing Association’s state chapter directory.

Many services operate Web sites with helpful career information and links to other resources in addition to online application materials and job postings. Here’s a sampling of national and international staffing companies and their main specialties:

Accountemps

Locations: 360 worldwide

Specialties: financial, accounting, credit and collections

Web site: www.accountemps.com

Aerotek

Locations: 150 worldwide

Specialties: engineering, aviation, scientific and architecture

Web site: www.aerotek.com

CLP Resources

Locations: 64 nationwide

Specialties: construction and skilled trades

Web site: www.clp.com

Kelly Services

Locations:  2,000 nationwide

Specialties: professional services, law, health care, technical and administrative

Web site: www.kellyservices.com

Labor Ready

Locations: 600 nationwide

Specialty: general day labor

Web site: www.laborready.com

Manpower

Locations: 4,200 worldwide

Specialties: professional services, technical, finance, engineering and administrative

Web site: www.manpower.com

MarketSource

Locations: serves clients nationwide from headquarters in Alpharetta, Ga.

Specialties: sales and marketing

Web site: www.marketsource.com

MSX International

Locations: 13 worldwide

Specialty: automotive business solutions

Web site: www.msxi.com

On Assignment

Locations:  79 worldwide

Specialties: health care, travel nursing and engineering

Web site: www.onassignment.com

ProLogistix

Locations: 62 nationwide

Specialties: logistics and warehousing

Web site: www.prologistix.com

TEKsystems

Locations: 90 worldwide

Specialty: information technology

Web site: www.teksystems.com

TransForce

Locations: 31 nationwide

Specialty: commercial truck drivers

Web site: www.transforce.com