Online battery usage calculator?
In the absence of an online tool, I can provide some alternatives.

As long as you're not considering any non-linear discharge effects, the following formula works fairly well:

$ I_\mbox{avg}=\sum{ I_{on} \times \frac{t_{on_j}}{t_{total}}} $

And then to find total battery life, you can divide the energy of the battery by the average current to get a time figure. 

$t_{life} = \frac{Capacity}{I_{avg}} $

So if we take your example to run some numbers through the formula, then we get:

$ I_{avg} = (5mA\times\frac{1ms}{1000ms}) + (30mA\times\frac{2ms}{1000ms}) = 65\mu A$

$t_{life} = \frac{2200mAh}{65\mu A} = 33846 \mbox{ hours} \approx 3.8 \mbox{ years}$

Now, before you down-vote me in a fit of rage for not having a link, I do know that this is not the question, and I strongly suspect that you understand how to run this calculation yourself. 

What I would suggest is that in the event that a handy internet reference is unavailable, that you would create a spreadsheet to calculate your power needs. This math is easily adapted to a spreadsheet calculation, and it allows real-time playing with the numbers. Given the simplicity, it may just be easiest to do things yourself. Arguably, it would take about the same amount of time, since the fundamental data must still be entered somehow into a computer.