This work describes and discusses the X-band Photoluminescence (PL) Detected Magnetic Resonance (PLDMR) of three small pi-conjugated molecules as powders, films, and solutions: 5,6,11,12-tetraphenyl tetracene (rubrene), Tris (8-hydroxyquinoline) Aluminum (Alq3), and 4,4'-Bis (9-carbazolyl) biphenyl (CBP);Rubrene exhibited both quenching and enhancing triplet resonances but lacked a detectable spin ½ polaron resonance. These triplet resonances changed over the course of time in both the powder and film samples. These changes appeared to be correlated with changes in their morphology or microstructure. In the powder, the relatively narrow quenching pattern weakened after the first measurement leaving the broad enhancing resonance. In the films, the resonance was initially enhancing but became quenching after "aging." It is suspected that the enhancing resonance results from nongeminate triplet-triplet annihilation to singlets in disordered domains. The quenching resonance is attributed to magnetic resonance-induced spin decorrelation of geminate triplet pairs in crystalline domains;Of the Alq3 samples studied, only the powder samples displayed resonances large enough for meaningful interpretation. The powder sample exhibited a weak enhancing spin ½ polaron resonance as well as both quenching and enhancing triplet resonances. As with typical polymers, the polaron resonance is thought to be enhancing due to nonradiative decay of polaron pairs, which reduces the rate at which they quench singlet excitons. The broad quenching triplet powder pattern at full-field may be the result of magnetic resonance induced spin decorrelation of geminate triplet pairs. The triplet pattern at full-field is enhancing, suggesting that a different process is occurring such as the nongerminate triplet-triplet annihilation to singlets;CBP powder exhibited a weak enhancing spin ½ polaron resonance which disappeared after the initial measurements. Also present initially and disappearing after time was a subtle broad quenching pattern at full-field. The triplet resonance at half-field was much more stable and allowed more measurements to be taken before becoming undetectable. The half-field triplet pattern has an unusual enhancing shape containing two distinct peaks which suggest that more than one type of triplet is present in CBP.