If you would like to learn more about trace fossils here are my references:

Books:
Richard G. Bromely. "Trace Fossils - Biology, taphonomy and applications." London: Chapman and Hall, 1996.
Stephen K. Donovan(editor). "The Paleobiology of Trace Fossils." Baltimore: The Johns Hopkins University Press, 1994.
Donald R. Prothero. "Bringing Fossils to Life - An Introductry to Paleobiology." Boston: McGraw-Hill, 1998.
 

Internet:
http://www.geo.arizona.edu/geo3xx/308/cha3.html
http://www.uc.edu/geology/geologylist/dinotracks.html
http://www.emory.edu/COLLEGE/ENVS/research/ichnology/
http://members.aol.com/paluxy2/ovrdino.htm
http://www.ucl.ac.uk/geolsci/edu/ugrads/fieldtrips/TraceFossils/tracefl.html