The Fermilab Tevatron proton-antiproton Collider operates at a center-of-mass energy of 1.96 TeV (the highest energy frontier). The dilepton channel is sensitive to deviations from the Standard Model predictions and could signal new physics. In this talk I will describe an analysis of events containing two high-p_T leptons, missing transverse energy and jets. The analysis strategy consists on selecting and understanding a dilepton sample based on one "tight" lepton (either an electron or a muon) and a "loose" lepton (a high p_T isolated track without lepton ID). Understanding the contribution coming from various physics backgrounds (which yield two real leptons) and fake backgrounds in which a parton or gluon fluctuate into an isolated track) is critical to this analysis. A wide range of kinematic regions (various jet E_T and track p_T cuts) have been explored. Preliminary top quark pair cross-section measurement will be presented using a 200/pb data sample collected by CDF in Run II.