looking for modern car thanks
You probably won’t find any in 1:29 but you will in 1:30 which is close enough.
Look under Die-cast models on eBay and do a search for 1:30.
The original Scalextric were 1:30.
King and Country military models are 1:30 but older styles.
Andrew
Diecast automobiles close to 1:29 would be 1:24 (20% too large) and 1:32 (9% too small).
Lots of modern stuff at http://www.collectablediecast.com/128-to-138-Scale_c_214.html
That’s the dealer I get my 1:24 cars from since 1:22.5 are rarer than hen’s teeth.
PS there are also ton’s of farm and military models in 1:32, some are diecast and others are plastic.
I agree that the 1:24 scale will most likely be the closest you will find.
There is a good selection here:
http://www.hobbylinc.com/diecast_model_cars_trucks_1:20-1:29_scale
If you look through the pages you will find some 1:27 pick up trucks
http://www.3000toys.com/ These folks have a pretty good selection of automobiles of all styles at pretty good prices. In their “Quick Search” function, select Cars and 1:32 or 1:27 ( a few) or 1:24 a lot to see what they have.
Good hunting.
Oh, oh, oh!!! I just found some 1:25 plastic models of some pretty interesting stuff, if you happen to bend that way. 
Vincent D’Agostino said:
I agree that the 1:24 scale will most likely be the closest you will find.
There is a good selection here:
http://www.hobbylinc.com/diecast_model_cars_trucks_1:20-1:29_scaleIf you look through the pages you will find some 1:27 pick up trucks
1:24 is by 20% too large; 1:32 is by 10% too small. Unless one puts the 1:32 right beside the 1:29 trains few people will notice. Less so from 10ft away.
Even the 1:24 stuff, placed strategically, looks fine from a galloping horse, just like my 1:24 freight stations do.
The price of perfection is insanity. 
What do you mean by “G” scale…?
Normally if you use the term “G” scale, people would think, 1:22.5
But,if you are wanting “Automobiles” to put into the USErains Auto Carriers, you should use 1:29.
This is the trouble with using the term “G” scale…better to just state the scale you want, then anyone caring, or able to help you, can give you the correct information
You can force perspective and use 1/24 up close and the 1/32 a few feet down the road and they will actually look good together
Well, Fred, he did say, 1:29. 
Steve Featherkile said:
Well, Fred, he did say, 1:29.
Fred gets grumpy when he wakes up during his long winter hibernation to soon…
Back to the cave, Fred…
thanks all
Michael,
I have a question, what do you call modern?
There is plenty of modern cars listed as 1:30 on eBay.
As far as modeling and scale goes if things are within 10% it is close enough for me, otherwise make your own or wait forever for someone else to make one.
Place different scaled models apart so they can’t be referenced against each other.
Another trick, if the scale available is larger, choose prototypes that are smaller in design or vice versa. That way the difference is not as obvious. For instance if you need a logging crawler for a 1:20.3 flatcar perhaps get a smaller Caterpillar 2 ton rather than a Caterpillar 20 ton in 1:16. Most wouldn’t tell the difference anyway.
You could probably get away with large prototype design vehicles in 1:32 to suit 1:29.
Andrew
Hold on a minute…
Mr.McCarthy, asked about “Automobile cars”…not automobiles…
…so I guess we should be directing him to the USTrains rolling stock…they have the newest ones, and used to have the old style too…and I did miss his mentioning 1:29…in the subject line…
Mark Dash said:
You can force perspective and use 1/24 up close and the 1/32 a few feet down the road and they will actually look good together
While that works well when taking pictures, it has its problems when you look at the layout and there is minimal depth to the scene (says he who built a few “minimal depth” dioramas).
Hans-Joerg Mueller said:
Michael,
I have a question, what do you call modern?
After the war?
Andrew
yes year 2000 or better