Standard doping concentrations for Si and GaAs Solar Cell (as well as other standard values)
Note: Question as originally posted asked about a photodiode, not a solar cell.

If you are not designing the device yourself, you don't need to know all those values. Most photodiodes you buy will simply have a dark current spec. If you need to know how this varies with reverse bias, you can work out Is from the dark current and the measurement conditions (V and T). 

For example, Fairchild QSD2030 specifies a dark current of 10 nA with 10 V reverse bias at 25 C. Given the specified reverse bias is so high, we know this dark current is essentially equal to Is, so we know Is ~= 10 nA.

Edit 

Okay, so you really want to get those values as an academic excercise.

A is just the area of the device. It can be whatever you design it to be.

Dn, Dp are the diffusion coefficients. You can get them from your textbook or from the Ioffe Institute

τn and τp are the carrier lifetimes. You can also find these values at the Ioffe Institute site.

Nd and Na are the donor and acceptor doping concentrations. You could design these however you like. Numbers between 1015 and 1020 are at least soft of reasonable.

The product NcNv is equal to ni2, the square of the intrinsic carrier concentration. You can also get this value from the Ioffe Institute on another page.