We present the results from a study of globular cluster systems belonging to three early-type galaxies : NGC 720 (E5), NGC 1023 (S0) and NGC 2768 (S0). The galaxies were observed in multi-band wide-field images using the Subaru and Canada France Hawaii Telescopes. For NGC 1023 and NGC 2768, we made use of archival HST data. This work is a first time investigation of globular cluster systems to large galactocentric radii (∼100 kpc) for NGC 720 and NGC 2768. The radial extent of globular cluster systems is characterised to be 68 ± 6 kpc for NGC 720, 20 ± 2 kpc for NGC 1023 and 63 ± 3 kpc for NGC 2768. We have determined the total number of globular clusters and hence the specific frequency for the individual galaxies. The azimuthal distribution of globular cluster systems are investigated and found to be similar to the host galaxy properties. We have examined for globular cluster bimodality and found the three galaxies have strong blue and red subpopulations. We also present a new correlation of globular cluster system sizes and host galaxy effective radii.