Last week, we had the author of TDD for a Shopping Website LiveProject. Friday at 11am Ranch time, Steven Solomon will be hosting a live TDD session just for us. See for the agenda and registration link
No. Horizontal scaling is something like adding extra webservers, adding new application servers to the clusters etc... there by increasing the scability. This is costlier when compared to vertical scaling.
Vertical scaling means that you increase the power of CPUs, RAMs in the existing hardware/systems. This may not scale well when compared to horizontal scaling.