解:$(1) $由$\begin{cases}{y=k}\\{y=\dfrac {k}{x}}\end{cases},$ 解得$x=1$
∴点$A_{0}$的坐标为$(1,$$0) $
$(2)$∵点$A_{0}、$$A_{1}、$$A_{2}$的横坐标为连续的整数
∴点$A_{1}、$$A_{2}$的坐标为$(2,$$0)、$$(3,$$0),$
即点$B_{1}、$$B_{2} $的横坐标分别为$2、$$3$
代入$y=\frac {k}{x} $求得$A_{1}B_{1}=\frac {k}{2},$$A_{2}B_{2}=\frac {k}{3}$
∴$\frac {C_{1}B_{1}}{A_{1}B_{1}}= \frac {k-\frac {k}2}{\frac {k}2}=1,$
$\frac {C_{2}B_{2}}{A_{2}B_{2}}= \frac {k-\frac {k}3}{\frac k{3}}=2 $
$(3) \frac {C_nB_n}{A_nB_n}=n$