Graco has a product called the SnugRider Infant Car Seat Stroller that does take some adjustments, but it can work as both though you can't just fold it up with the baby inside.
You can purchase a stroller car seat at Walmart, Target, Cook Brothers, Babies R Us, Kids R Us and you can also purchase a stroller car seat at Baby Depot.
Car seat strollers' prices vary, depending on where you get them. They generally range from around $50 to $300 (again, all depending on where you choose to buy the car seat stroller).
It is possible to buy Zooper strollers online from retailers like Sears and Amazon. It is also possible to purchase them from Stroller Depot, Baby Authority, and Goo Goo Boutique.
The best place to buy a Bob Jogging stroller would be on eBay. Many sellers offer shipping to the UK and there is a great selection available on the site.
The price you would pay for a stroller really depends on the model you buy and also what options you want to have in your stroller. I would recommend checking out reviews of different models before visiting a store to purchase one.
I would recommend the travel system. Most of them actually "grow with the baby" making it multiused throughout several years. The Graco Combi seems to have great reviews.
The best place to buy the BOB Jogging stroller is the buy a jogging stroller official site. They offer a variety of shipping prices and allow the user to search through the site for different models.
You can buy it at tagabikes.com or on Amazon.
You can buy it online. I would recomend amazone.com They will deliver the product at your house in just a few days. You also have some other sites like www.rei.com If you rather buy it there, it's possible.
Most companies would recommend buying baby equipment brand new and from the store. That being said, one can still buy cheap if you look for sales and use discount codes or coupons to purchase the stroller. If one chooses to buy a stroller second hand, it can be safe provided there are no broken parts, it is up to date, and there are no active recalls on the stroller.
You can buy a Quinny Speedi Stroller online from the Precious Little One website. Information about these strollers can be found at the official Quinny website.
One can buy a Britax Stroller directly from Britax themselves. One can also buy new and used ones at Amazon. For used strollers, eBay is always worth checking.