  We present Infrared Array Camera (IRAC) data and source catalogs from the
Spitzer Space Telescope Extragalactic First Look Survey. The data were taken in
four broad bands centered at nominal wavelengths of 3.6, 4.5, 5.8 and 8.0
microns. A set of mosaics and catalogs have been produced which are ~80%
complete and ~99% reliable to their chosen flux density limits. The main field
survey covers 3.8 deg^2, and has flux density limits of 20muJy, 25muJy, 100muJy
and 100muJy at wavelengths of 3.6, 4.5, 5.8 and 8.0 microns,respectively. The
deeper ``verification'' survey covers 0.25 deg^2 with limits of 10muJy, 10muJy,
30muJy and 30muJy, respectively. We also include deep data in the ELAIS-N1
field which covers 0.041deg^2 with limits of 4muJy, 3muJy, 10muJy and 10muJy,
respectively, but with only two wavelength coverage at a given sky position.
The final bandmerged catalogs contain 103193 objects in the main field, 12224
in the verification field and 5239 in ELAIS-N1. Flux densities of high
signal-to-noise objects are accurate to about 10%, and the residual systematic
error in the absolute flux density scale is ~2-3%. We have successfully
extracted sources at source densities as high as 100000 deg^-2 in our deepest
3.6 and 4.5 micron data. The mosaics and source catalogs will be made available
through the Spitzer Science Center archive and the Infrared Science Archive.
