"Total cost: 3*$400 million for the Shuttles
3* 100 million for the Titans
~2-5 billion development cost for the LEV, Hab etc.
3*200 million construction, testing, and maintenance for the LEV fleet
another 2-5 billion for Mission support and NASA Infrastructure."

Shuttle costs are 500-600 million- unless you counting marginal cost of about 100 million. I think 400 is generous- esp since the article is talking about modifing the Shuttle (gets me very worried:).
Titan IV are winding down or done- very expensive launch. Alternatives are Delta IV- H, Altas V (American Hvy launchers which could be ready for a lunar mission if NASA announced today that they were going- first launch is about a year from now), the cost is around 120 million per launch and can deliver more payload than Titan IV.
Non-American Hvy booster are Ariane V and Proton. Ariane V sells it's launch at about 120 million (to GEO). The Ariane is being modified so it can lift more payload to GEO (somewhere around 12 tons) more than Titan IV (6 tons to GEO). Proton lifts 20 tons to LEO, and somewhere around 30-50 million per launch- it's miserable for GEO since it's launching from such a high inclination (less than 2 tons). This is not such a high penalty if launching from this high inclination and going to Moon- somewhere around 5-6 tons to Lunar orbit (depends on higher stage rocket- probably safer to say it could get 6 tons to Lunar transfer orbit). Now Russia are talking with your country and Japan about launching Protons from Equator- this obviously gets more payload to GEO (same or more than Ariane V) and more to the Moon- at least 50% more than it can currently.
How you get to the Moon depends on who is going- what's their launch inclination. One solution to different inclinations is to "meet" at Earth/Moon L-1 or 2. The other is to "meet" in LEO at highest inclination of parties launching- 28 includes KSC [Shuttle, Altas V, Delta IV] but not Protons from Russian launch site [but from Equator, yes]. Another aspect is how do you get crew up in a man rated launch vehicle- only two vehicles are currently rated- shuttle and soyuz.
[French and Chinese are working on their own man rated launch vehicle].
For an America Moon mission, I assume for political reasons, you would use the Shuttle to get crew up and you would meet in LEO. I would only use Shuttle to get crew up- and put something in cargo bay- no sense wasting that lift capacity:). It would be nice to use soyuz since it's less than a 1/10 the cost, but it's got the lousy inclination. The French are working towards man rated launch for ISS, if done it could be used.

The cost of 2-5 billion for "the LEV, Hab etc" seems excessively high- probably could reduce this by a factor of 10- around 400 million. Of course it's certainly possible for a government to spend a lot of money and not build anything.

"I recognise the numbers are pretty rubbery, but that looks like $10-15 billion to me. That might be "cheap" in your book, but for that I suspect we could build a new heavy lift system, or at least build a docking adapter for the Energiya and get it all done quicker, cheaper, and safer."

The US govt. has already spent a couple billion developing new launchers:
http://www.boeing.com/defense-space/space/delta/deltahome.htm
http://www.ast.lmco.com/launch_atlas.shtml
Basically a couple billion "built" 1/2 dozen different launchers- cheap because they weren't made exclusively for some specific governmental mission- like going to the Moon or Mars, but they can be used for these purposes- maybe no manned Mars, but certainly Mars sample return.
You could do something "similar" with lunar landers- call them space tugs and/or extended habitional modules:).

"In your model, because you're using shuttle launches, each mission to the moon has a $1 billion penalty up front. How many of these do we need before it's cheaper to do it right and get a decent heavy lifter, which, btw, would just happen to make a manned Mars mission possible."

I agree, it's definitely using the Shutle too much and doesn't comprehend the pandora box of doing any modification to the Shuttle- maybe this could be done when Shuttle is truely operated privately. And once Shuttle is is more completely run by USA they maybe interested in modify it into a Shuttle-C- wouldn't need to cost tax payer hardly anything- say less than a billion in total including any modifications to launch pad

(Says he, running for cover)
[Lunar sirens sounding]
-gb