Suggested references

Tim Pearson's suggestions:

Marscher et al. 2008 Nature 452, 966 [BL Lac outburst]
Healey et al. 2008 ApJS 175, 97 [CGRaBS]
Healey et al. 2007 ApJS 171, 61 [CRATES]
Rudnick arXiv:0712.4268 [conference summary with pointers: ExtragalacticJets: TheoryandObservationfromRadiotoGammaRay]
Kellermann et al. arXiv:0708.3219
Lister arXiv:0707.0486  [Blazar demographics]
Ulrich et al 1997ARA&A..35..445U [AGN variability] - check the citations to this paper in ADS
 

Tony Readhead's suggestions:

Blandford, Netzer & Woltjer "Active Galactic Nuclei" (SAAS_Fee 20, 1990)

Begelman, Blandford & Rees "Theory of Extragalactic Radio Sources"  Rev. Mod. Phys., 1984, 56, 255.

Sterl Phinney, Ph.D. thesis, chapter 1.

Although these are all now somewhat out of date, they provide an excellent foundation for the study of AGN.


You should also find the following articles useful:

Bridle and Perley "Extragalactic Radio Jets" ARAA, 22, 319

Saikia and Salter "Polarization Properties of Extragalactic Radio Sources" ARAA, 26, 93

Readhead, A.C.S. 1994, Ap.J., 426, 51, "Equipartition Brightness Temperature and the Inverse Compton Catastrophe''

Readhead, A.C.S., Taylor, G.B., Xu, W., Pearson, T.J., Wilkinson, P.N., and Polatidis, A.G., 1996, Ap.J., 460, 612, "The Statistics and Ages of Compact Symmetric Objects''